There are not specific advantages for web pages, but for their components yes: from a performance point of view, serving images (and in general static contents) from different subdomains, will improve the rendering speed of the page. This because browsers limit parallel downloads to two images per domain, so if you have:
A part this, I can think to cookies: in past browsers were limiting to 50 to 300 cookies per domain, now the limit changed, but not for smartphones, where the limit is still low, so having multiple subdomains can help you to raise the number of usable cookies.
And there is a lot more if we consider load balancing. It depends a lot in your requirements.
how could i do this for my website....im developing an ecommerce site in which seller can show up their items...alibaba.com does the same.. if u are a shopkeeper and u have listed your products ,upon opening up of your site it will open as
companyname.en.alibaba.com..example like this:- http://nbassist.en.alibaba.com/...
also i have seen this on indian sites also...
can u tell me how must i develop my website architecture so that i can acomplish this above site architecture..
Nice questions! Its completely depend on how your web page is important and different from other web pages. E.g. if you have website www.abc.com and you're offering services like web design, SEO etc and apart from that you also offer production services like SEO tools, Website audit tools. So its better you do www.seotools.abc.com instead of www.abc.com/seotools. So your web page entity is completely different from whole website then you should create subdomain instead of domain folder. And if you're changing URL then do not forgot to redirect old URL to new one using 301 redirect.